1. Field of the Invention
The present invention relates to a refrigerator, and more particularly, to a refrigerator having a device for opening/closing cool discharge ports through which cool air is supplied into a cooling compartment.
2. Prior Art
In general, a refrigerator has a cabinet for forming a pair of cooling compartments, i.e., a freezing compartment and a fresh food compartment which are partitioned by a partitioning wall, a freezing compartment door and a fresh food compartment door for opening/closing the cooling compartments respectively, and a cooling system for supplying the freezing compartment and the fresh food compartment with cool air which is comprised of a compressor, a condenser and an evaporator. The cool air generated by the evaporator flows along a supply duct formed in a rear wall of each compartment, and then is supplied into each cooling compartment by a blowing fan through cool air discharge ports opened thereinto.
In such a conventional refrigerator, however, there exist an area on which the cool air discharged through the cool air discharge ports is concentrated, and an area to which a relatively small amount of cool air is supplied, so there occurs a deviation of temperature in the cooling compartments and uniform cooling cannot be achieved. Therefore, the refrigerator adopting so called tri-dimensional cooling method which has amended such a problem has been proposed. In the refrigerator adopting the tri-dimensional cooling method, the cool air discharge ports are provided at both sides walls as well as the rear wall of the cooling compartment in order to promote the uniform cooling.
However, in such a refrigerator adopting the tri-dimensional cooling method, since the cool air is discharged through the cool air discharge ports in fixed directions, there may be a dead-zone at an edge area which is not supplied with the cool air sufficiently. In particular, since the supply duct has to be provided not only in the rear wall but also in the side walls, there are problems that the space for storing food is reduced and the manufacturing cost increases due to the increased number of components and processes.
The uniform distribution of cool air has risen to an important problem in relation to the trend to use large-sized refrigerator.
In consideration of such a problem, the applicant of this invention has proposed a refrigerator having a device for dispersing cool air in International Patent Application WO 95/27278. FIGS. 1 through 3 are a side view, a partial enlarged sectional view, and an exploded perspective view of main elements of the refrigerator having the device for dispersing cool air.
The conventional refrigerator having the device for dispersing cool air has a pair of cooling compartments 2 and 3 in a cabinet 1, which are partitioned from each other by a partitioning wall 5. The cooling compartments 2 and 3 are called a freezing compartment 2 of relatively low temperature and a fresh food compartment 3 of relatively high temperature. On the front opening of the cooling compartments 2 and 3, doors 6 and 7 for opening/closing them are installed respectively. In the cabinet 1 is installed a cooling system comprising a compressor 11, a condenser (not shown), a freezing compartment evaporator 12a, and a fresh food compartment evaporator 12b. The cool air generated from the evaporators 12a and 12b is supplied to the corresponding compartments 2 and 3 by a freezing compartment fan 13a and a fresh food compartment fan 13b respectively.
A duct plate 9 of partial cylinder shape having cool air discharge ports 16 opened to the fresh food compartment 3 is attached to an inner wall plate 23 forming a rear inner wall surface of the fresh food compartment 3, and a supply duct 15 and a return duct 17 separated from each other by a seal plate 25 are provided between the duct plate 9 and a rear wall 4 of the cabinet 1. In the supply duct 15 is installed a duct member 21 for guiding the cool air blown by the fresh food compartment fan 13b downwardly. The cool air generated by the fresh food compartment evaporator 12b is blown by the fresh food compartment fan 13b, and then supplied to the fresh food compartment 3 via the supply duct 15 and the cool air discharge ports 16.
A cool air dispersing device 130 is installed in the supply duct 15. The cool air dispersing device 130 is comprised of a rotational shaft 131 having a vertical axis, cool air dispersing blades 132 assembled with the rotational shaft 131 in correspondence with the cool air discharge ports 16 respectively, and a driving motor 135 for rotating the rotational shaft 131. Each of the cool air dispersing blades 132 is comprised of three disc 136, 137 and 138 disposed in parallel with each other along the axis direction, and a first blade part 133 and a second blade part 134 disposed between the discs 136, 137 and 138. Each of the blade parts 133 and 134 are bent so that their cross section is a lax shape of alphabet S. The blade parts 133 and 134 are bent to the opposite directions to each other.
In the refrigerator having the above-described constitution, when the driving motor 135 rotates the rotational shaft 131 at a low speed, the cool air flowing along the supply duct 15 changes its flowing direction along the bent surface of the cool air dispersing blades 132, and is discharged into the fresh food compartment 3 to be dispersed horizontally. Meanwhile, when the concentrative cooling on a specific area is needed, the driving motor 135 stops the rotational shaft 131 in accordance with the direction of the cool air dispersing blades 132 so that the cool air is concentrated on the specific area.
However, in such a conventional refrigerator, the cool air discharge ports 16 are in open state always, so the cool air generated by the fresh food compartment evaporator 12b is always supplied into the fresh food compartment 3 irrespective of the temperature of the fresh food compartment 3. Thus, there is a problem that the fresh food compartment 3 can be overcooled. In particular, since a general refrigerator operates on the basis of the temperature of the freezing compartment 2, the possibility of overcooling of the fresh food compartment 3 always exists. More specifically, the compressor 11 begins to operate when the temperature of the freezing compartment 2 is higher than a temperature set by a user, by which the freezing compartment evaporator 12a as well as the fresh food compartment evaporator 12b generates the cool air. Accordingly, even though the temperature of the fresh food compartment 3 is lower than the temperature set by the user, the cool air is supplied into the fresh food compartment 3 through the cool air discharge ports 16, whereby the fresh food compartment 3 may be overcooled.